Electronic packages include for instance a device (semiconductor, processor or the like) coupled along a substrate having a plurality of layers and interconnecting traces and vias. The device is coupled with the substrate with a plurality of contacts that electrically couple the device and the substrate. In at least some examples the contacts include a solder interface of solder dots between the device and the substrate. The solder dots are heated after coupling of the device to the substrate. The heat reflows the solder with the goal of reinforcing the solder connection between the device and the substrate.
The application of heat, whether for reflow of the solder, testing of package function, or during installation of the package to another system, causes expansion of the substrate. The expansion, in at least some examples, warps at least the substrate and creates stress between the contacts including reflowed solder dots. In at least some examples the contacts are opened or provide a poor connection and the device or package fail to function properly.
In some examples, a glass cloth layer is included in the substrate to increase the stiffness of the package. In other examples, the package is pinned or clipped to an overall substrate to maintain the package in a flat orientation. In still other examples, a metal or polymer frame is formed around the package to increase stiffness.